Conventionally known as this kind of art is a laser processing method which irradiates a wafer-like object to be processed with laser light while locating a converging point within the object, thereby forming a plurality of rows of modified regions within the object along a line to cut and using the modified regions as a cutting start point (see Patent Document 1, for example).    Patent Document 1: Japanese Patent Application Laid-Open No. 2002-205180